1. Field of the Invention
This invention relates to an apparatus for assembling a cable drum used for winding of an elongated wire, an electric cable, an optical cable or the like.
2. Description of the Prior Art
Japanese Pat. No. 1089799 discloses in FIG. 1 thereof, a steel flange plate member a for a cable drum which has ribs b formed on its outside surface for increasing the mechanical strength thereof. The flange plate member a is formed into a flange plate i, as shown in FIG. 2, by welding an outer ring c thereto and by attaching an axial metallic member d to a center opening thereof. When a cable drum is to be assembled therefrom, the flange plate i is placed horizontally such that its inner surface is directed upwards, and a steel winding drum e is placed thereon and is welded at f for obtaining a sub-assembly g as shown in FIG. 3. Thereafter, this sub-assembly g is turned over and is placed on another flange plate i and is welded at h as shown in FIG. 4.
In the assembling of a cable drum by welding the winding drum e to the flange plates i as described, there is the problem that the attached positions of the flange plates i on both sides of the winding drum e may be out of alignment, and it takes a long time to assemble the drum. Further, a force is required to turn over the sub-assembly g. These problems result in a lowering of the workability.
Additionally, if the winding drum e of the resultant cable drum is not perfectly circular, the rotational balance thereof is spoiled when winding up a wire member at a high speed. Thus, it is desirable that the welding of the winding drum should be carried out while the winding drum is kept in the form of a perfect circle.